package com.psjj.demo1;

import java.util.ArrayList;
import java.util.Arrays;

public class Demo1 {
    public static void main(String[] args) {
        double pow = Math.pow(2, 4);
        System.out.println(pow);

        int[] arr = {1,2,3,4,5,6,7};
       /* int[] arr2 = new int[12];
        System.arraycopy(arr,1,arr2,3,1);
        System.out.println(Arrays.toString(arr2));*/
        //删除arr数组3下标内容
        int index = 4;
        System.arraycopy(arr,index+1,arr,index,arr.length-index-1);
        arr[arr.length-1] = 0;
        System.out.println(Arrays.toString(arr));
        ArrayList a = new ArrayList();
        a.remove(1);

    }
}
